Intergranular fatigue crack initiation in polycrystalline copper

0558727 - ÚFM 2023 RIV CH eng J - Journal Article
Chlupová, Alice - Šulák, Ivo - Babinský, Tomáš - Polák, Jaroslav
Intergranular fatigue crack initiation in polycrystalline copper.
Materials Science and Engineering A Structural Materials Properties Microstructure and Processing. Roč. 848, JUL (2022), č. článku 143357. ISSN 0921-5093. E-ISSN 1873-4936
R&D Projects: GA MŠMT LM2015069; GA MŠMT(CZ) LQ1601
Institutional support: RVO:68081723
Keywords : Extrusions * Fatigue crack * Grain boundary damage * Intergranular initiation * Intrusions
OECD category: Materials engineering
Impact factor: 6.4, year: 2022
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S0921509322007523?via%3Dihub

Polycrystalline copper specimens were fatigued in strain-controlled regime with high and low strain amplitude. Stress amplitude, plastic strain amplitude and hysteresis loops were recorded. The loop shape parameter reflecting the onset and evolution of the localization of cyclic plastic deformation was evaluated. Mechanism of intergranular fatigue crack initiation was studied on the electrolytically polished specimen surfaces using scanning electron microscopy coupled with focused ion beam. Intergranular cracks had initiated already at 4% of the fatigue life. Corrugated surface of grain boundary cracks close to the surface of the grains was closely related to the occurrence of the extrusions and intrusions produced on the grain boundaries. The observations give further support to the novel mechanism of grain boundary crack initiation based on the emergence of extrusions and intrusions on the grain boundary surface. Factors affecting the initiation of grain boundary cracks were identified.
Permanent Link: http://hdl.handle.net/11104/0332309